
In light of previous reviews, as soon as I opened the box I stuck each one into a breadboard and ran a basic test. I can't say if they meet all specs, but they work in the main modes, at least at close range, with no visible differences from other comparable modules purchased in the past. Also, all the boards I received had QFN ICs on board, none of the epoxy blobs that anyone has supposedly gotten in the past. This allowed me to graft one of the chips onto a custom PCB using a hot air tool, where it worked well.

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